Hi all just done pre site survey on a job found the following (never come across this before)
2 ccu's in the property 1 located next to the incoming head (A) and the other (B) is located approx 15 meters away
Both CCu's are feed via henley block. (A) tails are 25mm however the cable feeding (B) is 16mm 2 core non armoured double insulated PVC with no cpc. The run goes thought the fabric of the building there is no cpc run along side this cable!. There is also no isolator for that.
The cut out is 100amp the earthing arrangement is TNS.
Ze at (A) is 0.35
Ze at (B) is 0.63 (Just picking up paralel paths as there is visually no earth on that side of the building) all Zs on the (B) side are as expected very high 1.23 on sockets as an example.
The building is very old prob 200 years old with a newer extension added approx 1970's hence two dbs. The property is also in the middle of know where ie old farm house.
I want to ditch the 16mm feeding (B) and install 25mm swa via isolator etc etc. I am trying to find the reg (if it exisits) regarding the requirement of cpc in cables run though the fabric of a building so can back up my reason for running a new cable. OR would it be ok to run 16mm earth from the MET along side the current 16mm and install a fused 60amp double pole isolator. Haven't calculated VD on the 16mm yet just wanna run this by you guys for your opinion.
Let me know if I have missed any info that might help the answer...
Cheers
Kam
2 ccu's in the property 1 located next to the incoming head (A) and the other (B) is located approx 15 meters away
Both CCu's are feed via henley block. (A) tails are 25mm however the cable feeding (B) is 16mm 2 core non armoured double insulated PVC with no cpc. The run goes thought the fabric of the building there is no cpc run along side this cable!. There is also no isolator for that.
The cut out is 100amp the earthing arrangement is TNS.
Ze at (A) is 0.35
Ze at (B) is 0.63 (Just picking up paralel paths as there is visually no earth on that side of the building) all Zs on the (B) side are as expected very high 1.23 on sockets as an example.
The building is very old prob 200 years old with a newer extension added approx 1970's hence two dbs. The property is also in the middle of know where ie old farm house.
I want to ditch the 16mm feeding (B) and install 25mm swa via isolator etc etc. I am trying to find the reg (if it exisits) regarding the requirement of cpc in cables run though the fabric of a building so can back up my reason for running a new cable. OR would it be ok to run 16mm earth from the MET along side the current 16mm and install a fused 60amp double pole isolator. Haven't calculated VD on the 16mm yet just wanna run this by you guys for your opinion.
Let me know if I have missed any info that might help the answer...
Cheers
Kam
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